Direct evidence of adsorption induced Cr(II) mobility on the SiO(2) surface upon complexation by CO.
نویسندگان
چکیده
In situ, temperature dependent, XAFS proved that Cr(II) grafted on SiO(2) is extracted from the surface upon CO adsorption at 100 K: DeltaR(Cr-O) = +0.08 A. CO adsorption evolves into two coverage dependent steps: (i) displacement of weak siloxane ligands (non-classical carbonyls); (ii) relaxation of R(Cr-O) surface bond, R(Cr-CO) optimization and transformation into classical carbonyls.
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ورودعنوان ژورنال:
- Chemical communications
دوره 46 6 شماره
صفحات -
تاریخ انتشار 2010